Hydraulic press



2 Sheets-Sheet 1 R. W. DINZL HYDRAULIC PRESS INVENTOR P. W D/NZL .FiledDec. 23. 1953 7 & .ZL

June 29, 1 937.

June 29, 1937. R. w. DlNZL HYDRAULIC PRESS Fi1ed Dec. 25, 19:55

2 Sheets-Sheet 2 .i i 42 Vi il/197194! INVENTOR eMm/A ZL Patented June29, I937 HYDRAULIC PRESS Richard W. Dinzl, Narbert h, Pa., assignor toBaldwin-Southwark Corporation, a corporation 'of Delaware ApplicationDecember 23, 1933, Serial No. 703,863

2 Claims.

leakage from the hydraulic mechanism into the dry ice chamber. Variousarrangements have heretofore been proposed involving packing glands andthe like but have not met with the necessary degree of success either onaccount of the cost of manufacture or the inemciency of the 15arrangements.

It is one object of my invention to provide an improved arrangementwhereby .there is no possibility of the hydraulic actuating'fluidcontaminating the dry ice or other material that may be contained withinthe material chamber. Y A more specific object is to provide a materialchamber in combination with what is herein termed a cylinderram having aclosed end for engaging the material. A further object in this respectis to provide preferably a material receiving cylinder in which isdisposed a reciprocable hollow cylindrical ram having its innerendclosed while a stationary piston is disposed within the hollow ram. As aresult of this improved arrangement, the hydraulic fluid is containedwholly within the closed end of the ram without the use of any slidingjoint for sealing the interior of the ram from the material chamber,thereby completely eliminating the possibility of leakage into thematerial chamber.

Another object is to provide an improved ar-. rangement as abovedescribed wherein the ramcylinder is adapted to bev moved in oppositedirections by hydraulic pressure, or, to be moved 40 during the pressingoperation by hydraulic pressure but returned by admission of liquid orgaseous material in the material chamber.

Another object is to provide an improved press of the above type incombination with a structural arrangement of the press and a lowermovable platen for sealing and closing the lower end of .the materialchamber.

Other objects and advantages will be more apparent to those skilled inthe art from the following description of the accompanying drawings inwhich:

- Fig. 1 is a vertical sectional view through a press embodying myimprovements; Fig. 2 is a side elevation of the press of Fig. 1;

Fig. 3 is a modified form .of press employing a cylinder ram adapted tobe moved in opposite directions by hydraulic pressure.

In the particular embodiments of the invention which are disclosedherein merely for the purpose of illustrating certain specific formsamong'possible others that the invention might take, I have shown inFig. 1 a press having a base carrying a pair of joining columns 2 forsupporting a crosshead 3. A lower platen 4 is moved vertically by a ram5 supported in base I. Fluid pressure to this ram may be supplied fromany suitable and usual means such as a pump. Supported upon joiningcolumns 2 is a cylinder 6 having preferably a cylindrical materialchamber! whose lower end is open. The upperend of this cylinder isprovided with what might be termed an atmospheric packing gland 8.Reciprocably disposed in cylinder 6 is a cylinder-ram 9 whose lowerclosed end may be provided with a removable facing plate Hi. "This platedoes not necessarily have a leakproof fit with cylinder 6 as it does nothave 'to resist hydraulic actuating fluid. The upper end of ram cylinder9 has a shoulder I l adapted to engage, the upper collar l2 of thepacking gland when the ram cylinder is in its lowermost position to bedescribed later. The ram cylinder has an internal cylindrical bore I3 toreceive a stationary piston or ram element M. This piston is supportedby crosshead 3 and actuating fluid pressure is supplied from anysuitable source through a suitable valve controlled pipe I5 to thehollow interior of piston I4 or a suitable passage therein, whereby thefluid pressure may act upon the closed end of ram cylinder 9 to move thesame downwardly. A packing gland i6 is interposed between piston i4 andram cylinder 9. However, any hydraulic fluid that leaks past gland Itwill i not have direct access to the material chamber 1, and hence thereis no possibility of contaminating the material therein.

In operation of this form of press it is assumed that ram cylinder 9 isin its uppermost position as shown, whereupon fluid pressure is admittedto ram 5 to move platen 4 into sealing and closing contact with thelower end of cylinder 6. To insure a tight fit, the contacting surfacesof platen 4 and cylinder 6 may be ground or provided with a suitableseal. However, with the lower end of cylinder 6 closed, material such asliquid carbon dioxide or a combination thereof with carbon dioxide gasis admitted through an inlet port I'I until by a liquid gauge orpressure gauge it is determined that the'proper amount of mate! rial hasbeen admitted to chamber 1. Passage I1 is then closed and in accordancewith standard dry ice practice, a suction pump is attached to anotherpassage I8 to reduce the pressure in chamber 1, whereupon the liquidcarbon dioxide turns to the well-known form of snow. Thereupon hydraulicpressure is admitted thorugh pipe I! to the interior of ram cylinder 9to force the same downwardly and compress the material.

therein. During this pressing operation which requires a very highpressure, itis seen that the actuating fluid cannot pass through anypacking gland directly to the material chamber 1, and hence. nocontamination of the material can occur. When the block of material hasbeen fully compressed or formed, the pressure on ram is released by anysuitable valve mechanism, whereupon ram-cylinder 9 moves downwardly toeject the cake of material from the lower end of cylinder 6, duringwhich time the platen 4 moves downwardly. 'When the cake is fullyejected, shoulder l I will have come into engagement with element I! tothus limit the downward position of the ram-cylinder.

Inasmuch as no return piston area is provided for the ram cylinder 8, itis moved upwardly by first moving platen l and ram 5 upwardly to closethe lower end of chamber 1, whereupon liquid carbon dioxide and its gasare admitted through inlet H to chamber 1. The fit of cylinder ram 9 andplate III with cylinder 6 has suflicient clearance that the liquid orgaseous carbon dioxide under pressure may flow downwardly past ramcylinder 9 to the under side of plate In and thereby force the sameupwardly to the position shown in Fig. 1, whereupon the compressingcycle is repeated.

In the modification of Fig. 3 the same general arrangement of pressstructure is employed as shown in Fig. 1, and hence similar parts aregiven the same reference numbers. However, to provide for the hydraulicreturn of a ram cylinder 9', the piston M has a reduced portion as shownto provide an annular chamber 20. Hence it is seen that fluidpressuremay be admitted below plate 22 to force ram cylinder 9'downwardly whereas fluid pressure may be admitted through pipe II toannular chamber 20 to move ram cylinder 9' upwardly. Packing gland I6 iscompletely free from direct communication with material chamber 1 sothat any leakage of hydraulic fluid from annular chamber 20 cannotcontaminate the material. Piston plate l0? does not require a tightleakproof fit with its surrounding wall because. any leakage past thepiston into annular chamber Ill will merely flow outwardly through pipe2| which would be open to discharge during the pressing operation.

The mode of operation of this arrangement is the same as in the otherform except that the gas pressure of the material in chamber 1 is notused to move cylinder ram 9' upwardly but instead it is moved upwardlyby hydraulic pressure which is suitably controlled by any usualthree-wayvalve mechanism.

From theioregoing disclosure it is seen that in either form I haveprovided an extremely simple and yet highly efiective means wherebymaximum pressure may be applied to the material without danger ofcontaminating the same while at the same time there is obtained otherstructural and functional advantages which'will be more apparent tothose skilled in the art, these various features and any' other changesin structure or arrangement of parts being within thesplrit of theappended claims.

I claim:

1. A press comprising, in combination, means forming a material chamber,a cylinder-ram mounted for reciprocation within said chamber andprojecting therefrom at one end of the chamber, said ram. having aportion permanently disposed within said chamber, means forming asubstantially close fit between said chamber and cylinder-ram at saidend, said cylinder-ram having a closed pressure and and the other endbeing open, and a piston disposed in said cylinder-ram and projectingthrough said open end whereby actuating fluid pressure supplied betweensaid piston and said closed end is adapted to effect movement of the ramwithout leakage of actuating fluid into said material chamber.

2. A dry ice press comprising, in combination, a cylindrical materialchamber having one end open, a ram actuated platen adapted to close andseal said open end, a hollow ram reciprocable in said material cylinderthrough the other end thereof, one end of said hollow ram being closedto provide a material engaging surface, a piston disposed within saidhollow ram, said ram and material cylinder having clearance to permitflow of liquid or gas therebetween, and means providing an inlet to saidmaterial cylinder at a point where said hollow ram will overrun theinlet port, whereby liquid or gas pressure admitted into said inlet willflow through said clearance to said chamber and move said ram to areloading position.

RICHARD -W. DINZL.

